Answer
(a) : Acidic
(b) : Neutral
(c) : Basic
Work Step by Step
At 25$^{\circ}$C, the $K_w$ is $10^{-14}$, therefore:
$pH + pOH = 14$
$pOH = 14 - pH$
(a) $pOH > 7$
$14 - pH > 7$
$- pH > -7$
$pH < 7$
Therefore:
$pH < pOH$
$-log[H^+] < -log[OH^-]$
$log[H^+] > log[OH^-]$
Which means:
$[H^+] > [OH^-] : Acidic$
(b) pOH = 7
$14 - pH = 7$
$pH = 7$
Therefore: $pH = pOH$ : Neutral.
(c) $pOH < 7$
$14 - pH < 7$
$- pH < -7$
$pH > 7$
Therefore:
$pH > pOH$
$-log[H^+] > -log[OH^-]$
$log[H^+] < log[OH^-]$
Which means:
$[H^+] < [OH^-] : Basic$